<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <title></title>
    <link rel="stylesheet" href="bootstrap/css/bootstrap.min.css">
</head>
<body>
    <!-- doesnot work i frirefox -->
    <div class="container">
        <div class="embed-responsive embed-responsive-16by9">
            <iframe class="embed-responsive-item" src="http://www.baidu.com"></iframe>
        </div>
    </div>

    <div class="well well-sm">
        Look,i'm in a well.
    </div>
</body>
</html>